Why Shouldn't Leaves Be Burned?

When autumn comes leaves begin to turn yellow and dry, and finally fall to the ground. Then, people some times gather and bum them. might think it is a good way to keep the environment clean but actually, it isn't. When leaves are burning, harmful par-ticles will float in the air and might be easily absorded into the lungs.Those who breathe them in might feel dizzy,or like vomithing.Or,it might cause other internal diseases.To keep the air fresh and clean,leaves should not be burnt in residential areas.